Roads have been closed and a nearby pub evacuated due to worries over the structural safety of a former social club.
Emergency services closed off Gage Street and Mary Street to traffic, and access to Ffrances Passage in the city centre on Sunday afternoon, due to concerns over the closed down Collegian Club building on Gage Street.
The Tap House pub opposite, which is holding a music festival on Sunday, was evacuated.
The event - Roger's Rhythm Music Festival - is being held in aid of St John's Hospice, in memory of popular Morecambe man Roger Obertelli, with a line-up of bands until late on Sunday.
Bill Johnston, licensee of The Tap House, said the festival - which is being attended by Colin Hartley, mayor of Lancaster - has been moved to The Borough on Dalton Square.
"Sad news for us at The Tap House but very grateful to The Borough on Dalton Square, for so swiftly agreeing to accommodate at such short notice," said a post on The Tap House Facebook page on Sunday.
"Roger's Rhythm Music Festival is still taking place. The St John's Hospice card machine will be working and cash buckets on site."
The scene on Mary Street on Sunday afternoon. Photo: Joshua Brandwood
A Facebook post from Seven Sins restaurant on nearby Mary Street, on Sunday, said: "Just a heads up if you’re visiting us today, our lovely neighbours at The Tap House, or just wanting to get down Mary Street - there’s a large crack in the frontage of the Collegian Club so the fire service are in attendance and have closed the road for vehicles.
"We’re still open as normal so if you’re booked in, please allow some extra time."
The Collegian Club closed last year and is up for sale.
"Our colleagues at the fire service have requested that we close Gage Street in Lancaster due to concerns over the structural safety of a building," said a Lancaster Police spokesperson on Sunday.
A Lancashire Fire and Rescue Spokesperson said: "At 12:33 on 7th June, fire crews attended an incident on Gage Street, Lancaster, involving an unstable structure. Firefighters assessed the scene a before the incident was handed over to a building inspector.
"Crews were in attendance for approximately three hours."
A Lancaster City Council spokesperson said their Business Support team is working with Lancaster BID to support affected businesses.
If you have been affected you can contact them on business.support@lancaster.gov.uk.
"We’re also working with contractors to make the building safe, including installing structural scaffolding to secure the façade," said the spokesperson.
"Thank you for your patience and understanding while this work is carried out."
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